Any improvement in efficiency for any data retrieval operation in a distributed database has the potential to significantly improve operation, efficiency, and/or scalability of the distributed database. Indexes are conventional technology that is leveraged in almost every known database to improve efficiency of data retrieval. Typical database indexes include copies of certain fields of data that are logically ordered to be searched efficiently. For example, each entry in the index may consist of a key-value pair that represents a document or field (i.e., the value), and provides an address or pointer to a low-level disk block address where the document or field is stored (the key).